Your goal in this challenge, is to access the target host and perform the exfiltration of a PDF file containing the flag. For security reasons, the file extension has been removed. To avoid raising suspicion, this secret file is located in a hidden directory that can be found in the root user password. Find the root password, access the directory and exfiltrate the file containing the flag.
Your feedback is appreciated - Twitter: @mrhenrike. Thanks to Pedro Custodio for the idea.